1. Field of the Invention
The present invention relates to a method of canceling a location information request, and more particularly, to a method of canceling a location information request according to privacy information of a terminal whose location is to be tracked.
2. Description of the Related Art
In general, a mobile communication system provides a location service for delivering the location of a terminal (e.g., mobile station) to a specific entity periodically or according to a request by having a functional portion for calculating the location of a terminal in a mobile communication network.
Methods of calculating the location of the terminal include a cell-ID method of delivering the ID of a cell of the terminal, a method of calculating the location of the terminal by a triangular survey procedure after measuring the time it takes a signal wave to reach each neighbor base station from the terminal, a method utilizing a GPS (global positioning system) and so on.
In a related art location service, when a specific Location Service Client (hereinafter, a LCS client) periodically or immediately requests for a location information of a terminal, a location server calculates a location value by tracking the location of the terminal and then forwards it to the LCS client. At this point, the LCS client having requested for the location information may cancel the location information request.
However, in the event that it is impossible to track the location of the terminal whose location tracking is requested by the LCS client, the location server cannot cancel the location tracking request of the LCS client and also cannot provide location information of the terminal to the LCS client. Therefore, as the LCS client cannot know that the location server is unable to perform location tracking, it can continue to request for location information of the terminal if it is not provided with location information from the location server.
As seen from above, in the related art location service, although the LCS client having requested for location information of a specific terminal may cancel the request, nothing has been defined with respect to a method in which the location server having received a location tracking request from the LCS client that later cancels the location tracking request.
Consequently, in the case that the location server is unable to track the location of a terminal requested by the LCS client, there is a problem that a communication network is used inefficiently and the load of the location server increases since the LCS client continues to request the location server for location information of the terminal.